Re: VS2008 destroys static objects before global (non-static) objects?

On Wed, 22 Oct 2008 13:28:30 +0200, Ulrich Eckhardt <eckhardt@xxxxxxxxxxxxxx> wrote:

Boris wrote:
Can anyone confirm that the function _CRT_INIT has been changed from
VS2005 to VS2008 in such a way that static objects are now destroyed first
before global (non-static) objects are destroyed? Looking at the latest
C++ standard draft this seems to be permitted (and would explain why I see
a crash when closing a software which I just upgraded from VS2005 to
VS2008).

I can't confirm nor deny that particular change, but the initialisation
order of globals in different translation units has always been
unspecified, hence the so-called "initialisation order fiasco". Other than
that, objects are generally destroyed in the opposite order of their
creation and at least function-static objects are therefore always
destroyed before globals. What kind of static are you referring to?

My problem explained in pseudocode is this:

----------
template <typename T>
class memory_manager
{
public:
void *operator new(std::size_t) { return mem_p_.malloc(); }
void operator delete(void *p) { p_.free(p); }

private:
static pool p_;
};

class small_object : public memory_manager<small_object>
{
};

std::auto_ptr<small_object> o(new small_object());
----------

While the class definitions are in one DLL o is defined in another DLL (let's call them 1.dll and 2.dll where 1.dll depends on 2.dll). When the DLLs are loaded p_ in 2.dll is initialized first followed by an initialization of o and again p_ in 1.dll (at least that's what I see when stepping through the DLL initialization code; maybe I'm wrong here as I don't fully understand what Microsoft is doing there in crtdll.c and crt0dat.c). When the DLLs are unloaded everything is uninitialized but in reverse order. As the destructor of p_ is then called first which frees all memory managed by the memory manager I get an access violation when o is destroyed.

The code worked fine for years with VS2005 (and also g++ on Linux). If the initialization and destruction order was really changed in VS2008 I need to think about how to adapt the code. :-/

Boris
.

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